An immunohistochemical study of MAP2 and clathrin in gerbil hippocampus after cerebral ischemia

Changes in MAP2 and clathrin immunoreactivity were studied in gerbil hippocampus after transient cerebral ischemia. MAP2 immuno-reactivity decreased significantly by 1 h in the subiculum-CA1 and CA2 areas which correspond to reactive change, while no decrease was observed in CA1 until day 4. Before the initiation of delayed neuronal death, MAP2 immunoreactivity was not changed in CA1. On the other hand clathrin immunoreactivity increased in the pyramidal cell layer of CA1 by 3 h after ischemia and remained high for 2 days. Clathrin immunoreactivity in the pyramidal cell layer of CA1 diminished after delayed neuronal death. The transient change of clathrin was noted especially in CA1 in the period prior to delayed neuronal death. These results imply an abnormal change in clathrin turnover after ischemia, which may participate in the pathogenesis of delayed neuronal death.     

高效液相色谱法测定右旋儿茶素血浆浓度及药代动力学参数

本文建立了体液中右旋儿茶素的RP-HPLC测定方法。采用C_(18)键合相硅胶为填料的固相提取柱进行样品预处理,右旋儿茶素的提取回收率为79.8%.应用二极管阵列检测器对色谱峰纯度进行鉴定。该法精密度好,方法回收率近100%,日内、日间的变异系数为2.4～5.6%,血浓69.6～1160 ng/ml范围内呈线性关系,r=0.9993。家兔静注右旋儿茶素18mg/kg,其药代动力学过程符合二室模型,分布相半衰期为0.129 h,消除相半衰期为1.19h。     

Altered genetic response to beta-adrenergic receptor activation in late passage C6 glioma cells.

Previous studies have demonstrated variability in the phenotype of rat C6 glioma cells. In the present study, we compared morphology, growth rate, and beta-adrenergic regulation of gene expression in early (P39-47) and late (P55-90) passage C6 cells. Morphological changes were observed in five independently derived, late passage populations. In four of the five, the untreated cells were more polygonal than the fibroblast-like parental cells, and only a small fraction exhibited process outgrowth after dbcAMP treatment. Untreated cells from the fifth late passage population had longer cytoplasmic processes than parental cells and responded to dbcAMP with further process outgrowth. All late passage populations had shorter generation times than the parental cells. In early passage cells, treatment with the beta-adrenergic agonist, isoproterenol (IPR), resulted in an increase in c-fos mRNA and a decrease in c-jun mRNA (Gu-bits RM, Yu H: J Neurosci Res, 30:625-630, 1991). Both of these immediate early gene responses were irreversibly lost between P50 and P55. Additional differences in basal or IPR-induced mRNA levels were observed for beta-APP, GFAP, NGF, and PPE, but not for a number of other mRNAs. These results are discussed in relationship to previously described differences in the ability of early and late passage C6 cells to accumulate cAMP (Mallorga P, et al.: Biochim Biophys Acta 678:221-229, 1981).     

Antipeptide antibodies against the 5-HT1A receptor.

The availability of the primary amino acid sequence for a large number of molecules provides a fruitful opportunity for their cellular localization by utilizing the procedure of antipeptide antibody formation. This procedure permits a synthetic peptide sequence to be attached to a carrier molecule for the purpose of inoculating an animal to raise specific antibodies against the selected protein sequence. In this report we describe a number of steps that can be taken to increase the likelihood that the selected peptide sequence will be specific and antigenic. In addition, we describe how the peptides are synthesized, purified and coupled to keyhold limpet hemocyanin. The preparation of the antibody and its characterization are also presented in this method report. The immunocytochemical staining at both the light and ultrastructural level with serotonin (5-HT1A) receptor antipeptide antibodies is discussed. The advantages and disadvantages of this procedure are summarized.